recastnavigation/RecastDemo/Source/InputGeom.cpp

//
// Copyright (c) 2009-2010 Mikko Mononen memon@inside.org
//
// This software is provided 'as-is', without any express or implied
// warranty.  In no event will the authors be held liable for any damages
// arising from the use of this software.
// Permission is granted to anyone to use this software for any purpose,
// including commercial applications, and to alter it and redistribute it
// freely, subject to the following restrictions:
// 1. The origin of this software must not be misrepresented; you must not
//    claim that you wrote the original software. If you use this software
//    in a product, an acknowledgment in the product documentation would be
//    appreciated but is not required.
// 2. Altered source versions must be plainly marked as such, and must not be
//    misrepresented as being the original software.
// 3. This notice may not be removed or altered from any source distribution.
//

#include "InputGeom.h"

#include "ChunkyTriMesh.h"
#include "DebugDraw.h"
#include "Filelist.h"
#include "MeshLoaderObj.h"
#include "Recast.h"
#include "Sample.h"

#include <ctype.h>
#include <math.h>
#include <stdio.h>
#include <string.h>

#include <algorithm>

static bool intersectSegmentTriangle(const float* sp, const float* sq, const float* a, const float* b, const float* c, float& t)
{
	float v;
	float w;
	float ab[3];
	float ac[3];
	float qp[3];
	float ap[3];
	float norm[3];
	float e[3];

	rcVsub(ab, b, a);
	rcVsub(ac, c, a);
	rcVsub(qp, sp, sq);

	// Compute triangle normal. Can be precalculated or cached if
	// intersecting multiple segments against the same triangle
	rcVcross(norm, ab, ac);

	// Compute denominator d. If d <= 0, segment is parallel to or points
	// away from triangle, so exit early
	float d = rcVdot(qp, norm);
	if (d <= 0.0f)
	{
		return false;
	}

	// Compute intersection t value of pq with plane of triangle. A ray
	// intersects iff 0 <= t. Segment intersects iff 0 <= t <= 1. Delay
	// dividing by d until intersection has been found to pierce triangle
	rcVsub(ap, sp, a);
	t = rcVdot(ap, norm);
	if (t < 0.0f)
	{
		return false;
	}
	if (t > d)
	{
		return false;
	}  // For segment; exclude this code line for a ray test

	// Compute barycentric coordinate components and test if within bounds
	rcVcross(e, qp, ap);
	v = rcVdot(ac, e);
	if (v < 0.0f || v > d)
	{
		return false;
	}
	w = -rcVdot(ab, e);
	if (w < 0.0f || v + w > d)
	{
		return false;
	}

	// Segment/ray intersects triangle. Perform delayed division
	t /= d;

	return true;
}

static char* parseRow(char* buf, char* bufEnd, char* row, int len)
{
	bool start = true;
	bool done = false;
	int n = 0;
	while (!done && buf < bufEnd)
	{
		char c = *buf;
		buf++;
		// multirow
		switch (c)
		{
		case '\n':
			if (start)
			{
				break;
			}
			done = true;
			break;
		case '\r':
			break;
		case '\t':
		case ' ':
			if (start)
			{
				break;
			}
			// else falls through
		default:
			start = false;
			row[n++] = c;
			if (n >= len - 1)
			{
				done = true;
			}
			break;
		}
	}
	row[n] = '\0';
	return buf;
}

bool InputGeom::loadMesh(rcContext* ctx, const std::string& filepath)
{
	char* buffer;
	size_t bufferLen;
	if (!tryReadFile(filepath, &buffer, &bufferLen))
	{
		ctx->log(RC_LOG_ERROR, "buildTiledNavigation: Could not load '%s'", filepath.c_str());
		return false;
	}
	filename = filepath;

	delete chunkyMesh;
	chunkyMesh = nullptr;
	offMeshConCount = 0;
	volumeCount = 0;

	parseObjModel(buffer, bufferLen, verts, tris, normals);

	rcCalcBounds(verts.data(), getVertCount(), meshBMin, meshBMax);

	chunkyMesh = new ChunkyTriMesh;
	if (!chunkyMesh)
	{
		ctx->log(RC_LOG_ERROR, "buildTiledNavigation: Out of memory 'm_chunkyMesh'.");
		return false;
	}
	if (!chunkyMesh->TryPartitionMesh(verts.data(), tris.data(), getTriCount(), 256))
	{
		ctx->log(RC_LOG_ERROR, "buildTiledNavigation: Failed to build chunky mesh.");
		return false;
	}

	return true;
}

bool InputGeom::loadGeomSet(rcContext* ctx, const std::string& filepath)
{
	FILE* fp = fopen(filepath.c_str(), "rb");
	if (!fp)
	{
		return false;
	}

	if (fseek(fp, 0, SEEK_END) != 0)
	{
		fclose(fp);
		return false;
	}

	long bufSize = ftell(fp);
	if (bufSize < 0)
	{
		fclose(fp);
		return false;
	}
	if (fseek(fp, 0, SEEK_SET) != 0)
	{
		fclose(fp);
		return false;
	}
	char* buf = new char[bufSize];
	if (!buf)
	{
		fclose(fp);
		return false;
	}
	size_t readLen = fread(buf, bufSize, 1, fp);
	fclose(fp);
	if (readLen != 1)
	{
		delete[] buf;
		return false;
	}

	bool result = loadGeomSet(ctx, buf, bufSize);

	delete[] buf;
	return result;
}

bool InputGeom::loadGeomSet(rcContext* ctx, char* buffer, size_t bufferLen)
{
	offMeshConCount = 0;
	volumeCount = 0;

	char* src = buffer;
	char* srcEnd = buffer + bufferLen;
	char row[512];
	while (src < srcEnd)
	{
		// Parse one row
		row[0] = '\0';
		src = parseRow(src, srcEnd, row, sizeof(row) / sizeof(char));

		if (row[0] == 'f')
		{
			// File name.
			const char* name = row + 1;
			// Skip white spaces
			for (; *name && isspace(*name); ++name)
			{
			}
			if (*name)
			{
				if (!loadMesh(ctx, name))
				{
					return false;
				}
			}
		}
		else if (row[0] == 'c')
		{
			// Off-mesh connection
			if (offMeshConCount < MAX_OFFMESH_CONNECTIONS)
			{
				float* v = &offMeshConVerts[offMeshConCount * 3 * 2];
				int bidir;
				int area;
				int flags;
				float rad;
				sscanf(
					row + 1,
					"%f %f %f  %f %f %f %f %d %d %d",
					&v[0],
					&v[1],
					&v[2],
					&v[3],
					&v[4],
					&v[5],
					&rad,
					&bidir,
					&area,
					&flags);
				offMeshConRads[offMeshConCount] = rad;
				offMeshConDirs[offMeshConCount] = (unsigned char)bidir;
				offMeshConAreas[offMeshConCount] = (unsigned char)area;
				offMeshConFlags[offMeshConCount] = (unsigned short)flags;
				offMeshConCount++;
			}
		}
		else if (row[0] == 'v')
		{
			// Convex volumes
			if (volumeCount < MAX_VOLUMES)
			{
				ConvexVolume* vol = &volumes[volumeCount++];
				sscanf(row + 1, "%d %d %f %f", &vol->nverts, &vol->area, &vol->hmin, &vol->hmax);
				for (int i = 0; i < vol->nverts; ++i)
				{
					row[0] = '\0';
					src = parseRow(src, srcEnd, row, sizeof(row) / sizeof(char));
					sscanf(row, "%f %f %f", &vol->verts[i * 3 + 0], &vol->verts[i * 3 + 1], &vol->verts[i * 3 + 2]);
				}
			}
		}
		else if (row[0] == 's')
		{
			// Settings
			hasBuildSettings = true;
			sscanf(
				row + 1,
				"%f %f %f %f %f %f %f %f %f %f %d %f %f %d %f %f %f %f %f %f %f",
				&buildSettings.cellSize,
				&buildSettings.cellHeight,
				&buildSettings.agentHeight,
				&buildSettings.agentRadius,
				&buildSettings.agentMaxClimb,
				&buildSettings.agentMaxSlope,
				&buildSettings.regionMinSize,
				&buildSettings.regionMergeSize,
				&buildSettings.edgeMaxLen,
				&buildSettings.edgeMaxError,
				&buildSettings.vertsPerPoly,
				&buildSettings.detailSampleDist,
				&buildSettings.detailSampleMaxError,
				&buildSettings.partitionType,
				&buildSettings.navMeshBMin[0],
				&buildSettings.navMeshBMin[1],
				&buildSettings.navMeshBMin[2],
				&buildSettings.navMeshBMax[0],
				&buildSettings.navMeshBMax[1],
				&buildSettings.navMeshBMax[2],
				&buildSettings.tileSize);
		}
	}
	return true;
}

bool InputGeom::load(rcContext* ctx, const std::string& filepath)
{
	size_t extensionPos = filepath.find_last_of('.');
	if (extensionPos == std::string::npos)
	{
		return false;
	}

	std::string extension = filepath.substr(extensionPos);
	std::transform(extension.begin(), extension.end(), extension.begin(), tolower);

	if (extension == ".gset")
	{
		return loadGeomSet(ctx, filepath);
	}
	if (extension == ".obj")
	{
		return loadMesh(ctx, filepath);
	}

	return false;
}

bool InputGeom::saveGeomSet(const BuildSettings* settings)
{
	if (verts.empty())
	{
		return false;
	}

	// Change extension
	std::string filepath = filename;
	size_t extPos = filepath.find_last_of('.');
	if (extPos != std::string::npos)
	{
		filepath = filepath.substr(0, extPos);
	}
	filepath += ".gset";

	FILE* fp = fopen(filepath.c_str(), "w");
	if (!fp)
	{
		return false;
	}

	// Store mesh filename.
	fprintf(fp, "f %s\n", filename.c_str());

	// Store settings if any
	if (settings)
	{
		fprintf(
			fp,
			"s %f %f %f %f %f %f %f %f %f %f %d %f %f %d %f %f %f %f %f %f %f\n",
			settings->cellSize,
			settings->cellHeight,
			settings->agentHeight,
			settings->agentRadius,
			settings->agentMaxClimb,
			settings->agentMaxSlope,
			settings->regionMinSize,
			settings->regionMergeSize,
			settings->edgeMaxLen,
			settings->edgeMaxError,
			settings->vertsPerPoly,
			settings->detailSampleDist,
			settings->detailSampleMaxError,
			settings->partitionType,
			settings->navMeshBMin[0],
			settings->navMeshBMin[1],
			settings->navMeshBMin[2],
			settings->navMeshBMax[0],
			settings->navMeshBMax[1],
			settings->navMeshBMax[2],
			settings->tileSize);
	}

	// Store off-mesh links.
	for (int i = 0; i < offMeshConCount; ++i)
	{
		const float* v = &offMeshConVerts[i * 3 * 2];
		const float rad = offMeshConRads[i];
		const int bidir = offMeshConDirs[i];
		const int area = offMeshConAreas[i];
		const int flags = offMeshConFlags[i];
		fprintf(fp, "c %f %f %f  %f %f %f  %f %d %d %d\n", v[0], v[1], v[2], v[3], v[4], v[5], rad, bidir, area, flags);
	}

	// Convex volumes
	for (int i = 0; i < volumeCount; ++i)
	{
		ConvexVolume* vol = &volumes[i];
		fprintf(fp, "v %d %d %f %f\n", vol->nverts, vol->area, vol->hmin, vol->hmax);
		for (int j = 0; j < vol->nverts; ++j)
		{
			fprintf(fp, "%f %f %f\n", vol->verts[j * 3 + 0], vol->verts[j * 3 + 1], vol->verts[j * 3 + 2]);
		}
	}

	fclose(fp);

	return true;
}

static bool isectSegAABB(const float* sp, const float* sq, const float* amin, const float* amax, float& tmin, float& tmax)
{
	static const float EPS = 1e-6f;

	float d[]{sq[0] - sp[0], sq[1] - sp[1], sq[2] - sp[2]};
	tmin = 0.0;
	tmax = 1.0f;

	for (int i = 0; i < 3; i++)
	{
		if (fabsf(d[i]) < EPS)
		{
			if (sp[i] < amin[i] || sp[i] > amax[i])
			{
				return false;
			}
		}
		else
		{
			const float ood = 1.0f / d[i];
			float t1 = (amin[i] - sp[i]) * ood;
			float t2 = (amax[i] - sp[i]) * ood;
			if (t1 > t2)
			{
				float tmp = t1;
				t1 = t2;
				t2 = tmp;
			}
			if (t1 > tmin)
			{
				tmin = t1;
			}
			if (t2 < tmax)
			{
				tmax = t2;
			}
			if (tmin > tmax)
			{
				return false;
			}
		}
	}

	return true;
}

bool InputGeom::raycastMesh(float* src, float* dst, float& tmin)
{
	// Prune hit ray.
	float btmin;
	float btmax;
	if (!isectSegAABB(src, dst, meshBMin, meshBMax, btmin, btmax))
	{
		return false;
	}

	float p[]{p[0] = src[0] + (dst[0] - src[0]) * btmin, p[1] = src[2] + (dst[2] - src[2]) * btmin};
	float q[]{src[0] + (dst[0] - src[0]) * btmax, src[2] + (dst[2] - src[2]) * btmax};

	int cid[512];
	const int ncid = chunkyMesh->GetChunksOverlappingSegment(p, q, cid, 512);
	if (!ncid)
	{
		return false;
	}

	tmin = 1.0f;
	bool hit = false;

	for (int i = 0; i < ncid; ++i)
	{
		const ChunkyTriMesh::Node& node = chunkyMesh->nodes[cid[i]];
		const int* tris = &chunkyMesh->tris[node.i * 3];
		const int ntris = node.n;

		for (int j = 0; j < ntris * 3; j += 3)
		{
			float t = 1;
			if (intersectSegmentTriangle(src, dst, &verts[tris[j] * 3], &verts[tris[j + 1] * 3], &verts[tris[j + 2] * 3], t))
			{
				if (t < tmin)
				{
					tmin = t;
				}
				hit = true;
			}
		}
	}

	return hit;
}

void InputGeom::addOffMeshConnection(
	const float* spos,
	const float* epos,
	const float rad,
	unsigned char bidir,
	unsigned char area,
	unsigned short flags)
{
	if (offMeshConCount >= MAX_OFFMESH_CONNECTIONS)
	{
		return;
	}
	float* v = &offMeshConVerts[offMeshConCount * 3 * 2];
	offMeshConRads[offMeshConCount] = rad;
	offMeshConDirs[offMeshConCount] = bidir;
	offMeshConAreas[offMeshConCount] = area;
	offMeshConFlags[offMeshConCount] = flags;
	offMeshConId[offMeshConCount] = 1000 + offMeshConCount;
	rcVcopy(&v[0], spos);
	rcVcopy(&v[3], epos);
	offMeshConCount++;
}

void InputGeom::deleteOffMeshConnection(int i)
{
	offMeshConCount--;
	float* src = &offMeshConVerts[offMeshConCount * 3 * 2];
	float* dst = &offMeshConVerts[i * 3 * 2];
	rcVcopy(&dst[0], &src[0]);
	rcVcopy(&dst[3], &src[3]);
	offMeshConRads[i] = offMeshConRads[offMeshConCount];
	offMeshConDirs[i] = offMeshConDirs[offMeshConCount];
	offMeshConAreas[i] = offMeshConAreas[offMeshConCount];
	offMeshConFlags[i] = offMeshConFlags[offMeshConCount];
}

void InputGeom::drawOffMeshConnections(duDebugDraw* dd, bool hilight)
{
	unsigned int conColor = duRGBA(192, 0, 128, 192);
	unsigned int baseColor = duRGBA(0, 0, 0, 64);
	dd->depthMask(false);

	dd->begin(DU_DRAW_LINES, 2.0f);
	for (int i = 0; i < offMeshConCount; ++i)
	{
		float* v = &offMeshConVerts[i * 3 * 2];

		dd->vertex(v[0], v[1], v[2], baseColor);
		dd->vertex(v[0], v[1] + 0.2f, v[2], baseColor);

		dd->vertex(v[3], v[4], v[5], baseColor);
		dd->vertex(v[3], v[4] + 0.2f, v[5], baseColor);

		duAppendCircle(dd, v[0], v[1] + 0.1f, v[2], offMeshConRads[i], baseColor);
		duAppendCircle(dd, v[3], v[4] + 0.1f, v[5], offMeshConRads[i], baseColor);

		if (hilight)
		{
			duAppendArc(dd, v[0], v[1], v[2], v[3], v[4], v[5], 0.25f, (offMeshConDirs[i] & 1) ? 0.6f : 0.0f, 0.6f, conColor);
		}
	}
	dd->end();
	dd->depthMask(true);
}

void InputGeom::addConvexVolume(const float* verts, const int nverts, const float minh, const float maxh, unsigned char area)
{
	if (volumeCount >= MAX_VOLUMES)
	{
		return;
	}
	ConvexVolume* vol = &volumes[volumeCount++];
	memset(vol, 0, sizeof(ConvexVolume));
	memcpy(vol->verts, verts, sizeof(float) * 3 * nverts);
	vol->hmin = minh;
	vol->hmax = maxh;
	vol->nverts = nverts;
	vol->area = area;
}

void InputGeom::deleteConvexVolume(int i)
{
	volumeCount--;
	volumes[i] = volumes[volumeCount];
}

void InputGeom::drawConvexVolumes(struct duDebugDraw* dd, bool /*hilight*/)
{
	dd->depthMask(false);
	dd->begin(DU_DRAW_TRIS);

	for (int i = 0; i < volumeCount; ++i)
	{
		const ConvexVolume* vol = &volumes[i];
		unsigned int col = duTransCol(dd->areaToCol(vol->area), 32);
		for (int j = 0, k = vol->nverts - 1; j < vol->nverts; k = j++)
		{
			const float* va = &vol->verts[k * 3];
			const float* vb = &vol->verts[j * 3];

			dd->vertex(vol->verts[0], vol->hmax, vol->verts[2], col);
			dd->vertex(vb[0], vol->hmax, vb[2], col);
			dd->vertex(va[0], vol->hmax, va[2], col);

			dd->vertex(va[0], vol->hmin, va[2], duDarkenCol(col));
			dd->vertex(va[0], vol->hmax, va[2], col);
			dd->vertex(vb[0], vol->hmax, vb[2], col);

			dd->vertex(va[0], vol->hmin, va[2], duDarkenCol(col));
			dd->vertex(vb[0], vol->hmax, vb[2], col);
			dd->vertex(vb[0], vol->hmin, vb[2], duDarkenCol(col));
		}
	}

	dd->end();

	dd->begin(DU_DRAW_LINES, 2.0f);
	for (int i = 0; i < volumeCount; ++i)
	{
		const ConvexVolume* vol = &volumes[i];
		unsigned int col = duTransCol(dd->areaToCol(vol->area), 220);
		for (int j = 0, k = vol->nverts - 1; j < vol->nverts; k = j++)
		{
			const float* va = &vol->verts[k * 3];
			const float* vb = &vol->verts[j * 3];
			dd->vertex(va[0], vol->hmin, va[2], duDarkenCol(col));
			dd->vertex(vb[0], vol->hmin, vb[2], duDarkenCol(col));
			dd->vertex(va[0], vol->hmax, va[2], col);
			dd->vertex(vb[0], vol->hmax, vb[2], col);
			dd->vertex(va[0], vol->hmin, va[2], duDarkenCol(col));
			dd->vertex(va[0], vol->hmax, va[2], col);
		}
	}
	dd->end();

	dd->begin(DU_DRAW_POINTS, 3.0f);
	for (int i = 0; i < volumeCount; ++i)
	{
		const ConvexVolume* vol = &volumes[i];
		unsigned int col = duDarkenCol(duTransCol(dd->areaToCol(vol->area), 220));
		for (int j = 0; j < vol->nverts; ++j)
		{
			dd->vertex(vol->verts[j * 3 + 0], vol->verts[j * 3 + 1] + 0.1f, vol->verts[j * 3 + 2], col);
			dd->vertex(vol->verts[j * 3 + 0], vol->hmin, vol->verts[j * 3 + 2], col);
			dd->vertex(vol->verts[j * 3 + 0], vol->hmax, vol->verts[j * 3 + 2], col);
		}
	}
	dd->end();
	dd->depthMask(true);
}